Two-time grand slam winner Lleyton Hewitt can't work out why world No.2 Novak Djokovic has changed a winning formula ahead of this month's Australian Open.
Djokovic announced in December he had appointed three-time Wimbledon champion Boris Becker as his head coach, replacing long-time mentor Marian Vajda.
The Slovak had been Djokovic's coach since 2006, overseeing the 26-year-old Serb's six grand slam titles including four Australian Opens, three in the past three years.
While Vajda will remain a part of Djokovic's support staff, Hewitt said the switch to Becker had been the most surprising of several high-profile coaching appointments including Stefan Edberg and Ivan Lendl.
"I read somewhere that Marian is only - I don't even know if he's coming to Australia or not," Hewitt said.
"That's a little bit strange to me. I would have thought even if Becker was there and he was going to help out in ways, you know, Marian has obviously done a pretty good job and the success rate at Melbourne Park is pretty good."
Hewitt is not the first to express his surprise at Becker's new role, with Swiss great Roger Federer also expressing his shock at the German taking on his first top-level coaching job since retiring with six grand slam titles to his name in 1999.
The move was prompted as Djokovic aims to regain the world No.1 ranking following a year when he won one slam and had rivals Rafael Nadal and Andy Murray hitting top form.
Despite his shock at the move, Hewitt feels Djokovic should be given the benefit of the doubt.
"Obviously Novak knows his game pretty well," he said.
"He just wants that little bit of outside influence, and he thinks Boris can do it."